Leather-stretching machine



(No Model.) '4 SheetsSheet 1.

H. R. BEHRENS. LEATHER STRETGHING MACHINE.

Patented Feb. 24, 1891. I

l h. I

(No Model.) 4 Sheets-Sheet 2.

H. R. BEHRENS. LEATHER STRETGHING MACHINE.

. No. 446,847. Patented Feb. 24,1891. 4 1 I H.R .BEHRENS. LEATHER STRETGHING MACHINE.

4 Sheets-Sheet 3.

,(No Model.)

No. 446,847. Patented'Peb. 24, 1891.

(No Model.) ma -sneer. 4.

H. R. BEHRENS. LEATHER SI'RBTGHING MAGHINE.

No. 446,847. Patented'Feb. 24, 1891.

PATENT" OFFICE.

nENnY R. BEHRENS, on WORCESTER, MAssAonosETrs;nssrcnon TO ARTHUR M. TAFT, OF'SAME PLACE. I

LEATHER-STRETCHING MACHINE.

SPECIFICATION forming art of Letters Patent no. amma February 24,1891; J

I I Application filed Harsh 571890. Serial No. 342,113. (No model.)

To all whom it may concern:

Be it known that I, HENRY R. BEHRENS, of the city and county of Worcester, and State of Massachusetts, have invented certain new and useful Improvements in Leather-Stretching Machines; and I do hereby declarethat the following is a full, clear,'andexact description thereof, referencebeing had to the accompanying drawings, forming a part of this specification, and in which- I Figure l represents'a top or plan view of a leather-stretching machine embodying myimprovements. Fig.2 is a side view thereof with the main shaft in cross-section, looking in the direction indicated by arrow (1. in Fig. 1-. Fig.3 is an end view of the machine, looking in the direction indicated by arrow b in Fig. 1. tion of said machine, looking in the direction of arrow at; and Figs.5 and 6 are a longitudinal and transverse section, respectively, upon an enlarged scale, of part of the tensionregulating mechanism, hereinafter more fully described.

My invention is designed more especially for stretching leather to be used for belting;

and it consists in an improved construction.

and arrangement whereby. the leather is caused to be rubbed or racked back and forth with short reciprocating movements over and in contact with suitable racking frames to stretch said leather; also, wherebythe leather may be gradually drawn forward to keep it taut under a strong tension during said stretching operation, and said forward jtension discontinued after the leather has been properly stretched, all'by a'continuous and automatic operation, as hereinafter more fully set forth.

To enable others skilled in the art to which my invention appertains to better understand the nature and purpose thereof, I will now proceed to describe it more in detail.

In the drawings, A represents the main frame for supporting the racking-frames B B and the various operating parts of the mach-ine. The frame B is made stationary, being in' practice secured in any well-known way to the, main frame A, while the frame B is fitted to slide longitudinally in said main frame,

Fig. 4 is avertical longitudinal sec being provided upon each side with a horizontal longitudinal flange 0, (see dotted lines, Fig.

3,) adapted to fit in correspondingly-shaped grooves 01 in the main frame. It is operated by means of an eccentrice on the main shaft 0 through the long pawl f. connected at one. end with said eccentric and at its other end adapted to engage with the ratchet-teeth g on the. under side of the frame.- It is kept in engagement with said teeth byasuitablespringh,

succeeding notch or tooth in pushing the frame 6 5 forward by means of a stationary spring-pawl i, also adapted to engage with the teeth g. The purpose of said forward feed movement of frame B is to maintain at all times the same relative distance from the front end of the frame to the front fastening-point of the leather, so that said leather may be rubbed close up to the fastening during the stretching operation hereinafter described. Said stretching operation is performed by rubbing the leather under strong tension and down pressure back and forth longitudinally with short reciprocating movements over and in contact withthe upper edges of a series of transverse blades j, secured in the frames 13 B, said action being similar to that which would be produced if a person were stationed at each end of the leather, pulling back and forth with the leather taut, in opposite directions, with the ends below the level of the transverse bearings. V

The leather D is fastened at each end over the racking-frames B B in suitable clampdevices E and F, arranged on the large sliding frame or carriage G, fitted to-slide longi- 9o tudinally in suitable guideways in the main stationary frame A. Said carriage Gisoperated forward and back longitudinally, to pro-' duce the aforesaid reciprocating movements in stretching the leather, by means'of-a large 5 eccentric H, secured on-the main shaft C,

through the eccentric-strap H, fitted over said eccentric, and the eccentric-rod Lconnected at one end with said strap and at its opposite endwith a cross-piece or other suitable bear Ice ing 1 on the carriage G; Said eccentric ll not only operates the carriage G, but also, through said carriage and suitable connect-ions hereinafter described, the mechanism for pulling forward the front end of -the leather to keep said leather taut and under strong tension during the stretching operation. A V

The clamping device E consists of the slideto block E and eccentric-shaft E while the clamp device F consists of the slide-block l1" swivel-block F (pivoted at its front end to said slide-block by a vertical bolt 02,) and an eccentric-shaft F similar to shaft E Said eccentric-shafts are fitted to turn insuitable bearings E E on carriage G and operated in practice by means of suitable crank-levers.

. in securing the leather in the clamps the ends thereof are inserted between the eccen- 2o tries E F and blocks E F and said eccen- 0 the carriage and the slide-blocks of said clamps.

During the stretching operation the holding-pins for holding the front clamp F are removed to permit said clamp to be'forced 55 forward, as hereinafter described.

In stretching short pieces of leather part of the transverse bladesj at the rear or outer end of the stationary frame B are removed, as required, and in order that the clamp may 40 be kept in the same relative position to the blades (which are each made a little higher from the outer ends'ofthe frame toward the center of the machine) the guide-grooves 7.; are inclined upward (see Fig. 4) to correspond 5 with the general upward incline of the series of blades j at this end of the machine.

The purpose of pivoting the front clamp F so as to swivel, as aforesaid, is to permit the same to automatically adj ustitself to any unevenness in the, leather produced by the stretching operation. a

The slide-block F is moved forward with short and regular intermittent movements to keep the leather drawn taut under strong ten- 5 5 sion while being stretched by the return movementsof carriage G, each back movement of. the carriage causing the teeth of a large ratchet-wheel J, mounted thereon, to come in contact with the end of a horizontal pressure- 50 rod K, thereby turning said ratchet-wheel one tooth forward, and in consequence also moving said slide-block F one tooth forward through the shaft L, pinion M, internal segment-gear N,'external segment-gear O, and

rack P. The ratchet-wheel J and pinion M are secured on the horizontal transverse shaft bearings'on carriage 'G. Rack P is secured L, while the segment-gears N O are secured to'tho horizontal transverse shaft Q,both of which shafts are -fitted.to turn in suitable 7 to the under side of slide-block I and the segment-gear O is arranged to engage therewith, While the pinion M engages with thet other segment-gear N, as is fully 'shown in' Fig. 4 of the drawings.

The horizontal pressure-rod K is fitted to slide longitudinally in suitable bearings K, formed upon or secured to frame A, and a constant yielding forward pressure is imparted thereto by a weight S through suitable connect-ions engaging with the rear end of said rod. The forward inovement of the rod' is controlled by collarpr stop 0,adapted to bear against one of the bearings K or some i other iixed point on the machine. In this instance said connections consist of the long horizontal lever p, pivoted at its forward end to frame A and carrying the weight s at its opposite end, the vertical link q, pivoted at its lower end to the central part of said long lever p and at its upper end to the outer end of the horizontal arm 0f,a crank-lever r, and

said crank-lever, pivoted at its angle to a bear-' ing on frame A, and whose upper end has a bearing against the end of rod K. (See Figs.

1 and 2 of the drawings.) By this construction and arrangement it will be apparent that the rod K is held with a strong forward pressure, while atthe same time it is susceptible of being pushed back by an opposite pressure when said pressure is greater than the counter-pressure produced by the weight S.

The purpose of said mechanism.- is to provide means whereby the longitudinal tension upon the leather during the stretching operation may be automatically governed, so that said leather may not be improperly stretched.

Instretching a piece of leather, as D, it is first secured in position as taut as possible by hand with the slide-frame B close up to the stationary frame B and the segment-gears N O in the positions shown in Fig. 4. The power is then applied in the usual way, which causes the carriage Gto be moved back and forth to rub the under side of the leather 15 against the transverse blades j, at the same time causing the front clamp device F, as well as the slide-frame B, to be moved forward with short intermittent movements, as and for the purpose previously described.

The operation of rubbing and pulling with gradually-i ncreased longitudinal tension upon the leather is continued until it is stretched as much as it will bear without injury thereto, when said tension is discontinued and the stretched leather simply drawn back and forth over the transverse blades j without further stretching until the machine is stopped. The tension is discontinued when the resistance 7 of the leather in stretching is suflicient to" oyerbalance the counter-pressure produced by the weight 8 through its connections previously described. At this stage in the stretching operation, when the ratchet-wheel J comes in contact with the rod K the latter is pushed back by the. return movements of carriage G, consequently forcing back the upper. end of cran h-lever-rand lifting the weight S through said lever r and the other connections, as is spring-pawl J, arranged upon a suitable bearing on the carriage,-which is also adapted to engage with the teeth of the wheel. 'lheforward feed movements of slide-block 'F' be varied more or less by. changing the position of the stop on rod K and-turning the longitudinal screw 0' in or out of the rear end of said rod, and the duration of the stretching operation may also be varied by moving the weight S in or out on. its supporting-lever p. This adjustment is of advantage in treating different grades and sizes of leather.

The weight S may be held against longitndinal movement on its supporting-lever by extending a flange S up therefrom provided with a longitudinal opening for said lever, and Wllh a transverse opening to receive an eccentric-bolt S adapted to bear upon the top of the lever, and having a handle S for. turning the same to grip or release said weight to and from the lever.

A leatherstretching machine constructed as herein set forth and shown is strong and effective in use and requires but little attention in repairs and from I the attendant in running the same, while at the same time a superior grade of work is produced,the leather being thoroughly and uniformly stretched throughout its length close, up to the end fastenings.

Although the construction and arrangement herein shown and described are preferable in practice, I do not limit myself thereto, but reserve the right to make such modifications therein as may be desirable under different circumstances in carrying out the principle ofmy invention. 1

What I claim as new, and desire to secure by Letters Patent, is

1. A leather-stretching machine comprising, in combination, the following elements: a stationary frame secured to the main frame and a slide-fra me fitted to slide longitudinally in said main frame, said framesbeing arranged end to end lengthwise of the machine and-each having a series of transverse blades projecting upward therefrom, over which the leather may be rubbed, mechanism for bolding the leather by its ends in contact with the top edges of said transverse blades and for pulling said leather back and forth with short reciprocating movements in a taut condition and with a strong down pressure against said blades, mechanism for feeding forward the slide-frame aforesaid with short intermittent movements and for holding the same against back action, mechanism for feeding forward mayis fastened with short intermittent movements, also for prcventin g back action thereof, mechanism for controlling the speed and duration of .the last-described forwarth feed movement, and suitable supports for the vathe device to which the front end of the leather;

rions operatingparts,whereby the leather,

may be properly stretched by a continuous and automatic operation,substantially as set forth. .I I v 2. In Heather-stretching machine, the com- ,binatiomwith the main supporting-frame and its. actuating-eccentric operatively connected therewith-of a longitudinally -'reciprocatin g carriage fitted to slide in said frame, having suitable slide-blocks mounted on each end thereof, upon which are id turn mounted clamp devices for holding the ends of the leather to be stretched, the transverse racking-blades over which the leather is rubbed,

and mechanism connected withone-of the slide-blocks for feeding it.forward to. stretch the leather, substantially .as set forth. 3. In a leather-stretchin g machine, the combination, with the main supporting-frame, of a longitudmalty-reciprocating carriage fitted to slide in said frame and having clamp devices at each end for holding'the endsof the leather to be stretched, a stationary frame secured to the main frame, and a slideframe arranged end to end lengthwiseof the machine, and each having a series of transverse blades projecting up therefrom, said slide-frame being fitted to slide longitudinally in said main frame and having short intermittent forward, movements imparted to it, substantially as set forth. g

4. In a leather-stretchin g machine, the combination of the main frame with the stationary frame B, secured thereto, andthe slide frame B, fitted to slide longitudinally therein, and having means for moving the same forward with short intermittent movements, said frames B B beingarranged end to end lengthwise of the machine and each provided with a series of transverse-blades j, substantially and a suitable spring-pawl for preventing; back action'of said slide-frame, substantially 1 as and for the purpose set forth.

6. In a leather-stretching machine, the combination. of the main frame with the carriage G, fitted to slide longitudinally therein and having the clamp devices E F at each end 4 thereof for holding the ends of the leather, the eccentric II on shaft 0 and its connections with said carriage, said shaft, the stationary frame B, and frame B, having short intermittent forward movements, said frames being arranged end to end lengthwise of the machine and each 'having'a seriesof transverse blades y', substantially as and For the purpose set forth,

7 In a leather-stretching machine, the combil ati'on of frame A,carriage G,-fitted to slide longitudinally therein and having reciprocate ing movements imparted to it from an eccentric on the main shnftthrough suitable connections, the adjust-ableslide, clamp device E,

mounted on the rear end of the carriage, the

adjustable swivel, slide clamp device F, mounted on the forward end of said carriage and having a rack Pupon its under side, and

slide-rod K on the main frame, operatively connected with said rack p, substantially as and for the purpose set forth I 8. In a leather-stretching machine, the main frame A, frame B,'secure'd thereto, and frame B, fitted'to slide in said main frame, alsohaving short intermittent forward movements imparted theretofrom an eccentric on the main shaft through suitable connections and held against backaction by a suitable stationary spring-pawl, in combination with carriage G,

i fitted to; slide longitudinally in frame A and clamp device E, mounted onthe rear end of the carriage, the adjustable swivel slide-clam device F,'mounted on the forward end of said carriage and having a rack pupon its under side, and slide-rod K on-frame Ampera'tively' connected with said rack, substantia lly asand I for the purposes set forth.

ment gears .0 N and pinion M, shaftsQ L, fltted to turn in suitable-bearings in carriage G. ratch et-wh eel J, its springpawl,.and slide-rod K on the main frame, substantially as and for the purpose set,forth.,

10. In a leatherrstretching machingjhe ing'a. suitable holding-paw] and operatively connected with av clamp device F, substantially as described, in combiuatipnwith the adjustable slide-rod K, having a suitable stop,

and weight S, operatively connected wit-h said rod, substantially as and for the purposeset v forth.

' I 11. In a-leathenfstretohine .m3ichine, il\e I. combination of the weight S; .havinz an-upturned flange provided with a. longitudinal opening to receiveits supporting-levee ;and

with a transverse opening toreceive an ec centrio-bolt S with said lever. and eccentricbo, the latter being provided with means fortu rumg the. same, substantially as and for the purpose set forth.

v [is ratchet-wheel J, mounted on carriageG, hav- T v IIENRY R. B HRENS; ff 

